c# - 将字符串转换为 System.Data.SqlTypes.SqlBytes C#

Question

我有像 a="0xECBDE9721C47B" 这样的字符串变量，我想将这部分转换为 System.Data.SqlTypes.SqlBytes 类型的新变量。我需要的是解压缩该字符串中的值。

对于解压缩我想使用这个函数:

/// Decompressing the data
/// </summary>
[Microsoft.SqlServer.Server.SqlFunction(IsDeterministic = true, IsPrecise = true,
    DataAccess = DataAccessKind.None)]
public static SqlBytes BinaryDecompress(SqlBytes input)
{
  if (input.IsNull)
    return SqlBytes.Null;

  int batchSize = 32768;
  byte[] buf = new byte[batchSize];

  using (MemoryStream result = new MemoryStream())
  {
    using (DeflateStream deflateStream = 
      new DeflateStream(input.Stream, CompressionMode.Decompress, true))
    {
       int bytesRead;
       while ((bytesRead = deflateStream.Read(buf, 0, batchSize)) > 0)
         result.Write(buf, 0, bytesRead);
    }
    return new SqlBytes(result.ToArray());
  } 
}

Answer 1

也许你可以试试:

public static byte[] GetBinaryFromHexaString (string hexa)
{
    byte[] data = null;
    List<byte> bList = new List<byte>();
    try {
        for (int i = 2; i < hexa.Length - 1; i+=2) {
            string hStr = hexa.Substring(i, 2);
            byte b = byte.Parse(hStr, NumberStyles.HexNumber, CultureInfo.InvariantCulture);
            bList.Add (b);
        }
        data = bList.ToArray();
    }
    catch {}
    return data;
}

var sqlBytes = new System.Data.SqlTypes.SqlBytes (GetBinaryFromHexaString(a));

其中 a 是您的输入字符串，以 0x 开头。
之后您可以:

var decompressed = BinaryDecompress(sqlBytes);

---

编辑:
试试这个:

public static SqlBytes BinaryDecompress(SqlBytes input)
{
  if (input.IsNull)
    return SqlBytes.Null;

    var outputStream = new MemoryStream();
    using (MemoryStream result = new MemoryStream())
    {
        using (DeflateStream deflateStream =  new DeflateStream(input.Stream, CompressionMode.Decompress))
        {
            deflateStream.CopyTo(outputStream);
        }
    } 

    outputStream.Position = 0;
    return new SqlBytes (outputStream);

}

---

编辑 2:
我已经用你的 BinaryCompress 和 BinaryDecompress 试过了，对我有用。
我的测试代码:

    /// <summary>
    /// Compressing the data
    /// </summary>
    [Microsoft.SqlServer.Server.SqlFunction(IsDeterministic = true, IsPrecise = true, DataAccess = DataAccessKind.None)]
    public static SqlBytes BinaryCompress(SqlBytes input)
    {
        if (input.IsNull) return SqlBytes.Null;

        using (MemoryStream result = new MemoryStream())
        {
            using (DeflateStream deflateStream =
                   new DeflateStream(result, CompressionMode.Compress, true))
            {
                deflateStream.Write(input.Buffer, 0, input.Buffer.Length);
                deflateStream.Flush();
                deflateStream.Close();
            }
            return new SqlBytes(result.ToArray());
        }
    }

    /// <summary>
    /// Decompressing the data
    /// </summary>
    [Microsoft.SqlServer.Server.SqlFunction(IsDeterministic = true, IsPrecise = true, DataAccess = DataAccessKind.None)]
    public static SqlBytes BinaryDecompress(SqlBytes input)
    {
        if (input.IsNull) return SqlBytes.Null;

        int batchSize = 32768;
        byte[] buf = new byte[batchSize];

        using (MemoryStream result = new MemoryStream())
        {
            using (DeflateStream deflateStream =
                   new DeflateStream(input.Stream, CompressionMode.Decompress, true))
            {
                int bytesRead;
                while ((bytesRead = deflateStream.Read(buf, 0, batchSize)) > 0)
                    result.Write(buf, 0, bytesRead);
            }
            return new SqlBytes(result.ToArray());
        }
    }


    public static string GetHexaStringFromBinary (byte[] data)
    {
        string hexData = "0x";
        for (int i = 0; i < data.Length; i++) {
            hexData = string.Concat (hexData, data[i].ToString("X2"));
        }
        return hexData;
    }


    public static byte[] GetBinaryFromHexaString (string hexa)
    {
        byte[] data = null;
        List<byte> bList = new List<byte>();
        try {
            for (int i = 2; i < hexa.Length - 1; i+=2) {
                string hStr = hexa.Substring(i, 2);
                byte b = byte.Parse(hStr, NumberStyles.HexNumber, CultureInfo.InvariantCulture);
                bList.Add (b);
            }
            data = bList.ToArray();
        }
        catch {}
        return data;
    }

以及用法:

string originalStr = "This is a test string!!";
byte[] data = Encoding.ASCII.GetBytes (originalStr);
SqlBytes sbCompressed = BinaryCompress (new SqlBytes (data));

string a = GetHexaStringFromBinary (sbCompressed.Value);
//a = 0x0BC9C82C5600A2448592D4E21285E292A2CCBC74454500

var sqlBytes = new SqlBytes(GetBinaryFromHexaString (a));
SqlBytes deCompressed = BinaryDecompress (sqlBytes);
string finalStr = Encoding.ASCII.GetString (deCompressed.Value);
//finalStr = "This is a test string!!"

希望对你有帮助